Production of organo-aluminum compounds



United States Patent 3,291,819 PRODUCTION OF ORGANO-ALUMINUM COMPQUNDS Giinther Bruno, Philadelphia, Pa., and Hubert Schirp, Dusseldorf, Germany, assignors to I-Ienkel & Cie, G.m.b.H., Dusseldorf-Holthausen, Germany, a corporation of Germany No Drawing. Filed Apr. 20, 1961, Ser. No. 104,241 Claims priority, application Germany, Apr. 23, 1960, H 39,254; May 17, 1960, H 39,451 7 Claims. (Cl. 260-448) This invention relates to a novel process for the production of aluminum alkyl compounds from metallic aluminum, hydrogen, and olefins with the double bond in a position other than the terminal position. The invention further relates to the production of aluminum alkyl compounds wherein the alkyl radicals are primary alkyl radicals. The invention further relates to the production of primary alcohols and the production of a-olefins from HOD-OL-OlBfiIlS.

The preparation of aluminum trialkyls or dialkyl alum inum hydrides in which the alkyl radicals are primary alkyl radicals from metallic aluminum, hydrogen and otolefins is well known. However, it has been repeatedly stressed in the prior art that the reaction would operate only with a-olefins and that it would not work with olefins with the double bond in a position other than the terminal position. Some of the articles of interest in this respect are Z. Angew. Chem, vol. 68 (1956), p. 727; Suomen Kemistilehti, A30 (1957), p. 110; Brennstoff-Chemie, vol. 40 (1959), p. 210; Ann., vol. 629 (1960), pp. 8, 144; Dissertation by Weyer, Techn. Hochschule Aachen (1956), p. 1; and Dissertation by Pfohl, Techn. Hochschule Aachen (1957), pp. 14.

In applicants copending application Serial No. 82,156, filed January 17, 1961, there is described a process for the preparation of hydrocarbon compounds of aluminum from olefins in which the double bond is in a position other than the DC-pDSltiOn. In the first step of this process, the above mentioned olefins are reacted with aluminum hydrocarbons which contain at least two alkyl radicals in the molecule at elevated temperatures and under those conditions which facilitate the displacement of the original alkyl radical from the aluminum hydrocarbon. Preferred aluminum alkyls for this process are those which have the general formulas wherein R and R are identical or different hydrocarbon radicals which may also together form a hydrocarbon ring, and further wherein the alkyl radicals contain preferably from 4 to 6 carbon atoms. Typical representatives of these aluminum alkyls are aluminum triisobutyl or dibutyl aluminum hydride.

The organo-aluminum compounds with secondary alkyl radicals obtained in the first step may be isomerized in a second step at elevated temperatures into compounds with primary alkyl radicals which may, for example, serve as starting materials for the preparation of primary alcohols.

It has now been found that to prepare aluminum primary alkyl compounds and a-olefins from olefins whose double bonds are in a position other than the a-pOSitiOn it is not necessary to start with other aluminum alkyl compounds.

It is an object of the invention to provide a novel process for the production of aluminum secondary alkyl compounds from aluminum, hydrogen and olefins with a 7 double bond in a position other than a terminal position.

3,291,839 Patented Dec. 13, 1966 It is another object of this invention to provide a novel process for the production of aluminum alkyl compounds in which the alkyl radicals are primary alkyl radicals. It is a further object of this invention to provide a novel process for the production of a-olefins from olefins whose double bond is in a position other than the OL'POSltiOII.

Another object of the invention is to provide a process for the production of primary alcohols from olefins whose double bond is in a position other than the a-position.

These and other objects and advantages will become obvious from the following detailed disclosure.

The process of the invention comprises reacting olefins with a double bond in a position other than the terminal position, metallic aluminum and hydrogen at elevated temperatures and pressures to form di-secondary alkyl aluminum hydrides. These secondary alkyl compounds are isomerized by heating at elevated temperatures of at least C. to form aluminum primary alkyl compounds. Said aluminum primary alkyl compounds are cleaved by heating at elevated temperatures to form Otolefins.

The olefins which are used as starting materials for the process of the invention have the formula wherein R and R may be the same and are alkyl radicals and R is selected from the group consisting of hydrogen and an alkyl radical, and the sum of the carbon atoms of R, R and R is between 3 and 28. The alkyl radicals may be straight chained or branch chained radicals, but it is preferred to employ olefins in which at least one of the alkyl radicals is a straight chain radical because of the isomerization step. The preferred olefins are those in which R is a hydrogen atom, at least one alkyl radical is a straight chain alkyl radical, and which contains 5 to 30 carbon atoms. Examples of suitable starting materials are pentene-3, heptene-3, octene-4, nonene-4, decene-5,'

dodecene-3, dodecene-4, dodecene-6, hexadocene-6, hexadocene-7, octadecene-9, eicosene-IO, octacosene-14, and the like. The amount of olefin in the reaction is advan tageously 2 to 20 moles, preferably 4 to 6 moles per mole of aluminum.

For the commercial operation of the process it is preferred to use technical grade mixtures of hydrocarbons which contain olefins with a non-u double bond, possibly in admixture with paraffins and with u-olefins. Such mixtures are, for example, obtained from the Fischer- Tropsch synthesis or by catalytic cracking of petroleum. In many cases it is advantageous to employ these mixtures in the form. of fractions having a certain chain length.

The presence of parafiins in the starting material does not interfere with the reaction according to the invention. Instead, the parafiins represent desirable diluents for the second reaction step as their presence suppresses side reactions.

The OL-Ol6fil'lS contained in the starting material react with greater speed than the olefins having the double bond in other than the terminal position and therefore react preferentially. It may be advantageous to first react the tit-Olefin contained in the mixture and thereafter to distill 01f the unreacted hydrocarbon mixture from the reaction mixture and use this distillate again for the reaction.

Further, it is often advantageous to remove, prior to the reaction, compounds with functional groups present in the technical grade hydrocarbon mixture, especially compounds with active hydrogen, which are capable of 0 reacting with the organo-aluminum compounds under the of small amounts of impurities and instead assume certain losses in yield.

The aluminum to be used in the reaction must be sufficiently active. Its surface must not be coated with an oxide layer as the inert oxide coating will make the aluminum inactive.

Certain types of finely divided aluminum have recently come on the market which may be employed as such. In general, however, it is advantageous to activate the aluminum. The activation may be accomplished in accordance with various known methods. Thus, the aluminum may be comminuted, for example milled, under exclusion of oxygen and preferably in the presence of an aluminum alkyl compound. Molten aluminum, which has been produced by spraying in an inert stream of gas or by distillation in a high vacuum and rapid cooling of the distillation vapor, may also be employed. Furthermore, alkyl halides, such as ethyl bromide or aluminum alkyl halides, may be used for the purpose of activation. The methods for activation of aluminum which may be used are summarized by K. Ziegler in Liebigs Annalen der Chemie, vol. 629 (1960), pp. 45.

The aluminum is preferably employed in excess although stoichiometric or less amounts may be used. In general, an excess of 10-20% may be used.

It is further advantageous to add to the reaction mixture small amounts of organo-aluminum compounds as catalysts. For this purpose, it is advantageous to employ those organo-aluminum compounds which are to be produced in each case. The speed of reaction is notably accelerated even by small amounts of these catalysts. Most advantageously, the catalysts are used in an amount of about 12-10%, based on the amount of the product to be produced. Alkyl aluminum halides may also be employed as catalysts. If desired, these alkyl aluminum halides may also be formed in the reaction mixture itself by addition of alkyl halides to the reaction mixture.

The hydrogen is advantageously used under elevated pressure. The speed of reaction is particularly favorable at a pressure above 100 atmospheres. Basically, however, it is also possible to work at considerably lower pressures. At a pressure of more than 300 atmospheres, the hydrogenation of the olefin takes preference to an increasing degree. For these reasons, it is generally advantageous to operate at a hydrogen pressure between 100 and 300 atmospheres.

The reaction is carried out at elevated temperatures, preferably at about 90150 C. Above 150 C. a hydrogenation of the olefin takes place to an increasing degree. Most advantageously, the reaction is carried out at a temperature between 'l00130 C.

In order to suppress the undesirable hydrogenation, it is advantageous not to heat the entire amount of olefin at the beginning together with the aluminum and hydrogen, but instead to feed the olefin or the olefin mixture batchwise or continuously into the reaction vessel. It has been found, however, that even without these auxiliary measures the hydrogenation of the olefin occurs to a lesser degree than with a-olefins. Thus, the reaction is generally performed by first heating the aluminum, the hydrogen and a portion of the olefin together, and then gradually adding the remainder of the olefin. If the hydrogen pressure drops below 160 atmospheres, additional hydrogen is advantageously introduced under pressure.

The end of'the reaction is recognized by the fact that the hydrogen pressure stays at a substantially constant value. Thereafter, the reaction mixture is allowed to cool, the excess hydrogen is removed and then, if desired, the mixture may be subjected directly to the second reaction step, preferably after removing any large quantities of unrecated aluminum which may be present. However, the reaction product may also be isolated by removal of the residual aluminum and distilling 01f excess olefin as well as any solvent or diluent which may be present, if necessary.

The di-secondary alkyl aluminum hydrides produced in the first step of the process have the formula wherein R, R and R have the above definitions is transformed into alkyl aluminum compounds with primary alkyl radicals by heating in the presence of olefins. In addition to the rearrangement of the secondary alkyl radicals into primary alkyl radicals, a complete or very substantial addition of another alkyl radical takes place, so that the reaction products consist entirely or to a large part of trialkyl aluminum compounds and contain only minor amounts of aluminum-H-bonds. The third alkyl radical is present entirely or partially in primary form, depending upon the prevailing temperature and the duration of the heating step.

This reaction takes place at a temperature between and 250 C., preferably at a temperature between 180 and 220 C. The duration of the heating step depends upon the temperature and the structure of the reactants and may vary between a few minutes and several hours.

The olefin is preferably the same olefin with a non-abond which is used as the starting material for the first process step. This olefin does not undergo any undesira'ble changes under the prev-ailing conditions, so that the excess may readily be recovered.

It is also possible to use an ot-olefin as the olefin. In this case a dimerization of the olefin often takes place, so that the third alkyl radical which is added to the aluminum compound entirely or partly contains twice the number of carbon atoms as the (X-Olefin starting material.

The olefin which simultaneously serves as a stabilizing agent in this step is, therefore, advantageously employed in excess above the amount required for formation of the third alkyl radical, that is in an amount of more than one mol per mol of the di-secondary alkyl aluminum hydride. While there is no upper limit for the amount of olefin present as stabilizer, it is recommended to use no more'than 20 mols of olefin per mol of di-secondary alkyl aluminum hydride for convenience and economy.

In place of the di-secondary alkyl aluminum hydrides it is also possible to use as starting materials for the second process step those compounds which are obtained by reaction of the di-secondary aluminum hydrides with an a-olefin at temperatures below 150 C. In this manner trialkyl aluminum compounds are formed in which two alkyl radicals are secondary and the third alkyl radical is primary. These aluminum tri-alkyl compounds have the formula In this formula R, R and R have the above indicated definitions and Alk is a primary alkyl radical with 2 to 30 carbon atoms.

If the reaction product of the second step still contains Al-H-bonds it is possible to react these Al-H-bonds with an a-olefin and in this manner to obtain a reaction product which consists exclusively of trialkyl aluminum compounds. The subsequent reaction of Al-H-bonds which may be present with an a-olefin is especially advantageous if it is desired to obtain high molecular alcohols from the trialkyl aluminum compound by oxidation and subsequent hydrolysis. In this case the Al-H-bonds which are still present give rise to side reactions and thereby reduce the yield of alcohol.

The first and second steps of this process may be done in one operation, and the di-secondary alkyl aluminum hydrides need not be separated first.

The novel di-secondary alkyl aluminum hydrides have not been previously described in the literature.

Isomerization reactions have heretofore been described only with short chain aluminum alkyls, namely, aluminum tri-isopropyl, and aluminum tri-secondary butyl. These compounds were rearranged into the corresponding nalkyl compounds by heating for 30 hours at a temperature between 110 and 130 C. However, partial splitting off of the alkyl radicals took place and side reactions occurred. Even by raising the reaction conditions, good results could not be obtained. Therefore, it is surprising that the rearrangement of applicants di-secondary alkyl aluminum hydrides may be easily and with quantitative yields isomerized to straight chain alkyl compounds.

The aluminum primary-alkyl compounds produced by the second step, are cleaved in the third step of the process at elevated temperatures and under conditions such that the olefin split off thereby is rapidly removed from the reaction mixture. For this purpose it is possible to employ reduecd pressures and/or an entraining agent. The selection of the reduced pressure depends generally upon the boiling point of the olefin formed by the reaction. For example, the decomposition of aluminum n-octyl is advantageously performed under a vacuum of about to 20 mm. mercury at 150 to 220 C. For the pyrolysis of aluminum tri-n-dodecyl it is advantageous to use a vacuum of about 1 mm. mercury and a temperature of 150 to 220 C. With increasing chain length of the alkyl radicals, it is advantageous to perform the 'decomposition in a thin layer evaporator. Thus, it is possible to decompose aluminum tri-n-octadecyl in such a thin layer evaporator at about 150 to 300 C. and a pressure of about 10- mm. mercury and to obtain virtually pure a-octadecene thereby. The same method may be used in the case of organo-aluminum compounds with still longer alkyl radicals containing up to about 30 carbon atoms.

An inert gas, such as nitrogen, argon or hydrogen, may be used as the entraining agent. This gas is heated to the decomposition temperature and passed through the organo-aluminum compound at a sufiiciently high rate of fiow to insure the rapid removal of the olefin. It may also be advantageous to use the vapor of an inert solvent, such as a hydrocarbon, as the entraining agent. The solvent should have a boiling point of about 170 to 220 C. at the pressure selected for the pyrolysis.

It is possible, and in some instances advantageous, to perform the cleavage in two steps. In the first step 1 mol of olefin is split off under mild conditions and a di-alkyl aluminum hydride is formed. The latter is decomposed in the second step at elevated temperature into aluminum hydride and olefin. Since the isomerization of the third alkyl group in the first step of the cleavage is in some instances not quite complete, the olefin distillate of the first cleavage contains certain amounts of olefins with a nonterminal double bond, whereas the olefin distillate in the second step consists practically of pure a-olefin.

It has further been found that the pyrolysis of the organo-aluminum compound may be enhanced by addition of small amounts of aluminum powder or finely granulated aluminum. The decomposition of the aluminum hydrocarbons is thereby accelerated and undesirable side reactions are suppressed. It suffices to add quantities of less than 1%, such as 0.2 to 0.5%, of aluminum powder to the organo-aluminum compound, although larger amounts may be used.

The or-olefins produced in accordance with the process of the invention are of high purity. They may be employed for those various purposes for which a-olefins have previously also been employed. For example, by polymerization they yield excellent lubricating oils which exhibit a considerably higher viscosity index than the products produced by polymerization of olefins having a double bond in other than the terminal position.

Despite the strong isomerizing effect of finely divided aluminum or aluminum hydrocarbons, it is surprising that it is possible to produce substantially pure tar-olefins, more than 95% a-olefins. In other processes for the production of pure a-olefins, mixtures containing 2 to 6% of other isomers are obtained and is even higher in some industrial processes.

The aluminum primary-alkyl compounds produced by the isomerization may be readily converted into products such as primary long chain alcohol, carboxylic acids or alkyl sulfonic acids, for example, the primary alkyl compounds may be oxidized to form the aluminum alcoholate which then may be hydrolyzed to produce the free alcohol. By using the process of the present invention, olefin mixtures obtained from the Fischer-Tropsch synthesis of catalytic cracking of petroleum can now be converted into valuable products whereas previously only the a-olefin could be utilized.

In the following examples there are described several preferred embodiments to illustrate the invention. However, it should be understood that the invention is not intended to be limited to the specific embodiments.

Example I To the extent necessary, all of the operations described in the tests below were carried out in an atmosphere of nitrogen.

20 gm. of finely granulated aluminum, 37 gm. of aluminum tri-n-dodecyl (produced according to the process of applicants copending application Serial No. 82,156), cc. of dry hexane and 30 gm. of pure dodecene-6 were milled for twenty hours in a V3M steel ball mill having a capacity of 0.9 liter which was about half filled with steel balls. Thereafter, the mixture was transferred into a shaker autoclave having a capacity of 1 liter. 130 atm. of hydrogen were introduced into the autoclave under pressure and the autoclave was heated to 120 C. while shaking it, whereby a pressure of about atm. developed. Subsequently, 333 gm. of dodecene-6 were pumped into the autoclave in about seven equal portions with the aid of a metering pump at intervals of one hour. After addition of the last portion of dodecene-6, the pressure was about 330 atm. The autoclave was then maintained for an additional nine hours at a temperature of 120 C., whereby the pressure dropped to about 280 atm.

After cooling of the autoclave, the excess hydrogen was released. Thereafter, small residual amounts of unreacted aluminum were removed from the reaction mixture by filtration through a G4 frit. Y

The solvent and the excess dodecene were distilled in vacuo at a bath temperature up to 100 C. from the slightly brown, clear filtrate. Toward the end, a vacuum of 10* mm. mercury was applied.

By fractionation, 149 gm. of dodecene-6 containing dodecane were recovered from the distillate. The iodine number of the recovered dodecene was 136. This shows a content of about 10% dodecane.

After removal of the solvent and the excess dodecene, the reaction product weighed 262 gm. Its aluminum content was 7.2% (theoretical value of di-secondary dodecyl aluminum hydride: 7.35%). Upon reaction with npropanol, a sample of the substance developed about 90% of the amount of hydrogen calculated for di-secondary dodecyl aluminum hydride.

For further identification, 78 gm. of the reaction product were heated together with 25 gm. of heptene-l for sixteen hours at 65 C. accompanied by agitation with a magnetic stirrer. Subsequently, the alkyl aluminum compound was diluted with 1 liter of dry heptane and was then oxidized in accordance with known methods with dry oxygen. Thereafter, the volatile components were distilled off. The residue weighed 107 gm. By hydrolysis with the calculated amount of dilute sulfuric acid, 102 gm. of a mixture were obtained which consisted essentially of higher alcohols and ketones. Fractional distillation of this mixture in a 1 meter packed column furnished the following fractions.

7 18 gm. of heptanol-l:

B.P. at 12 mm. Hg=75.5 C. n 1.4242 OH number=478 20.5 gm. of C ketones:

B.P. at 12 mm. Hg=117-119 C. 38 gm. of secondary dodecanols:

B.P. at 12 mm. Hg=126127 C. OH number=286 7 gm. of dodecanol-l:

B.P. at 12 mm. Hg=140 C. n =1.4408 M.P.=23-24 C. OH number=298 147 gm. of the alkyl aluminum compound, together with 140 gm. of the recovered dodecene-6 containing dodecane and 350 cc. of dry hexane, were heated under a nitrogen pressure of 10 atm. in a shaker autoclave with a 1 liter capacity for 26 hours at 170 C. After cooling and releasing the internal pressure from the autoclave, the reaction product weighing 517 gm. was filtered through a G frit. The hexane as well as the excess dodecene were distilled out of the filtrate at a reduced pressure up to 10- mm. mercury anda bath temperature up to 100 C. 90 gm. of dodecene-6 with an iodine number of 136 were recovered from the distillate by fractional distillation.

The reaction product, which weighed 195 gum. and contained 5.4% aluminum, yielded about 24% of the amount of hydrogen calculated for di-primary dodecyl aluminum hydride upon hydrolysis of a sample. 150 gm. of this compound were heated together with 23 gm. of heptene-l for sixteen hours at 65 C. accompanied by stir-ring with a magnetic stirrer. Then, after diluting the reaction product with 1.5 liter of heptane, it was oxidized in the manner described above, and the alcoholate obtained thereby was hydrolyzed. Upon fractional distillation of the alcohol mixture thus obtained in a 1 meter packed column, the following fractions were obtained.

9.0 gm. of heptanol-l:

B.P. at 12 mm. Hg=75.5 C. n =L4242 110 gm. of dodecanol-l:

B.P. at 12 mm. Hg=140 C. n =l.44-l M.P.=24 C.

Example II In the following experiment, all the operations were performed under nitrogen, where so required.

27 g. aluminum pellets, 1.5 gm. aluminum stearate, 8 gm. aluminum tri-isobutyl and 100 m1. dry hexane were ground for 20 hours in a steel ball grinder. 0n completion of the grinding process, the mixture was transferred to a 1-liter agitator autoclave. The clear liquid on top of the ground aluminum was again siphoned off as much as possible. To the 65 gm. residue remaining in the autoclave, 50 gm. dodecene-, 1.5 gm. aluminum stearate and 10 gm. aluminum tri-isobutyl were added. The autoclave was subjected to hydrogen at the pressure of 115 atmospheres. The autoclave was agitated and heated to 120 C., whereby the pressure rose to 150 atmospheres. 364 gm. dodecene-G in 12 portions were pumped into the autoclave at half-hour intervals, with the aid of a metering pump. After the addition of the last portion, the pressure was adjusted to 305 atmospheres. The autoc'lave was then maintained for an additional 13 hours. After this period, the pressure was constant and amounted to 220 atmospheres.

After cooling of the autoclave, the pressure was released. The product was filtered through a 6-4 frit. The residue of non-converted aluminum amounted to 8 gm. The solvent and the non-reacted dodecene-6 were distilled from the filtrate first at normal pressure at 100 C., then under vacuum at 12. mm. mercury and lastly under vacuum at 10- mm. mercury. The weight of the raw product was 237.5 gm. It consisted of virtually pure aluminumdi-sec.-dodecyl hydride.

60 gm. aluminum-di-sec.-dodecyl hydride were heated for 20 hours with 120 gm. dodecene-6 at a temperature of 180 C. in an apparatus having a magnetic agitator. The dodecene-6 was then removed by distillation under high vacuum at 10- mm. mercury. The maximum bath temperature reached 100 C. The weight of the distillate was 112 gm. The distillation residue came to 66 gm. A sample of the substance developed with n-propanol 87% of the hydrogen quantity calculated for aluminum-di-n-dodecyl hydride.

For purposes of conversion into aluminum tri-n-dode cyl, 92 gm. of this product were heated for 16 hours with 39 gm. dodecene-l at 70 C. in an apparatus having magnetic stirring. The crude reaction product obtained in this manner was vacuum-distilled to free it from volatile fractions and was then transferred to a high-vacuum distilling apparatus, for pyrolysis. By reason of the development of hydrogen, the vacuum oscillated during this operation between 10' and 1 mm. mercury.

The first step in the pyrolysis was performed at a bath temperature of 165 C. 27 gm. of the distillate were obtained. The re-disti-llation of this quantity yielded 22 gm. of a distillate with the following characteristics.

Boiling point at 12 mm. Hg=8892 C. 14 1.4321 Iodine number=148 According to IR analysis, the distillate contained approx. of alpha-olefin. In the second stage of pyrolysis, the bath temperature was slowly raised to 260 C. 51 gm. distillate were obtained. The re-distillation of this quantity yielded 40 gm. of a distillate having the following characteristics.

Boiling point at 12 mm. Hg=8992 C. n =1.4324 Iodine number==149 According to IR analysis, the distillate contained approximately 98% of :x-olefin.

Example III In the experiment described hereunder, all the operations were performed under nitrogen, where so required.

40 gm. aluminum pellets, 1.5 gm. aluminum stearate, 8 gm. aluminum di-isobuty-l hydride and 100 ml. dry hexane were ground for 15 hours in an 0L9-liter steel ball mill, approximately half-filled with steel balls. The mixture was next transferred to a 1-liter agitator autoclave. The liquid was again siphoned off as much as possible. There was a residue of 80.4 gm. in the autoclave. To this residue was added 40 gm. nonene-4, 1.5 gm. aluminum stea-rate and 8 gm. aluminum di-isobutyl hydride. Hydro-gen pressure was applied at atmospheres and the autoclave washeated to 120 C., stirring, whereby the pressure attained atmospheres. 380 gm. nonene-4 in 16 portions were pumped at half-hour intervals into the autoclave with the aid of a metering pump. After addition of the last portion, the pressure came to approximately 330 atmospheres. The autoclave was turned off after 22 hours, after attaining a constant pressure of 225 atmospheres. After cooling the autoclave, the excess hydrogen was released. The product was filtered through a G4 frit. The residue of non-converted aluminum amounted to 9.5 gm.

The solvent and the excess nonene-4 were removed from the filtrate by distillation, first at normal pressure at a bath temperature of up to 100 C., then at 12 mercury at a bath temperature of up to 60 C. and lastly, at 0.1 mm. mercury at a bath temperature of up to 80 C. The Weight of the distillation residue came to 336.5 gm. It consisted of virtually pure aluminum di-sec.- nonyl hydride.

102 gm. of the aluminum di-sec.-nonyl hydride obtained in the foregoing manner were heated to 70 C.

for 15 hours with 66.8 gm. tetradecene-l, in an apparatus with magnetic stirring. Next, the aluminum alkyl compound was diluted with 1.4 liters of dry hexane and oxidized in known fashion with dry oxygen. The volatile fractions were removed by distillation at normal pressure and, later on, under vacuum at 12 mm. mercury. The maximum bath temperature was 100 C. There was a residue of 172 gm. of the oxidation product. By hydrolysis with a calculated quantity of dilute sulfuric acid and subsequent extraction, 156 gm. were obtained of a mixture consisting essentially of nonanol and tetradecanol and ketones, Fractional distillation of this mixture in a l-meter rotary column yielded the following fractions.

15.7 gm. nonanone-3:

Boiling point at 11 mm. Hg=7076 C. n =1.4195 CO number=376 42.4 gm. nonanol-4: 1

Boiling point at 11 mm. Hg=8791 C. n =1.4294 OH number=372 11.6 gm. intermediate fraction:

Boiling point at 11 mm. Hg=124-124.5 C. 11 5 1.4305 Iodine number=l2.2

45.3 gm. tetradecanol-l:

Boiling point at 11 mm. Hg=165 C. n =1.4388 OH number=258 100 gm. of the aluminum di-sec.-nony1 hydride were heated at reflux for 20 hours at 164 C. together with 89 gm. nonene-4. Next, the excess nonene-4 was removed by distillation, first under water-jet vacuum at 12 mm. mercury, then under oil-pump vacuum at 0.1 mm. mercury. The maximum bath temperature reached 70 C. The weight of the distillate was 50.6 gm. 136.9 gm. were left over as a distillation residue. For the purpose of converting the residual Al-H bonds into Al-R bonds, the distillation residue was heated with 17.5 gm. dodecene-l for 15 hours, in an apparatus having magnetic agitation, to 70 C. After dilution with 1.3 liters of dry hexane, the mixture was oxidized in the customary manner with dry oxygen. The hexane was removed by distillation. The residue consisted of 163.6 gm. of the oxidation product. This was hydrolyzed with the calculated quantity of dilute sulfuric acid. Extraction with ether yielded 145 gm. of a mixture of nonanol, dodecanol and ketones.

By fractional distillation of 126 gm. of the mixture so obtained, the following fractions were secured from a l-meter rotary column.

5.1 gm. largely ketone:

Boiling point at 11 mm. Hg=52-84 C. n =1.419l CO number=230 83.9 gm. nonanol-l:

Boiling point at 11 mm. Hg=103-104 C. n =1.4333 OH number=384 9.66 gm. dodecanol-1:

Boiling point at 11 mm. Hg=140-141 C. n =1.4400 OH number=296 Example IV In the following experiment, all the operations were performed under nitrogen, where 50 required.

24 gm. aluminum pellets, 1.5 gm. aluminum stearate, 8 gm. aluminum di-isobutyl hydride and 100 ml. dry hexane were ground for 15 hours in an 0.9-liter steel ball mill, about half-filled with steel balls. The mixture was next transferred to a 1-liter agitator autoclave. The hexane was again siphoned off as much as possible. 57

gm. of residue were left in the autoclave. Added to this were 81 gm. of docosene containing a non-terminal double bond, 1.5 gm. aluminum stearate and 12 gm. aluminum di-isobutyl hydride. Hydrogen was admitted at atmospheres and the autoclave was heated to 120 C. while stirring, whereby the pressure rose to 132 atmospheres. Next, 323 gm. of docosene (IR analysis had shown that the docosene used contained only approximately 1% of a-olefin) in 13 portions were pumped into the autoclave at half-hour intervals, with the aid of a metering pump. After addition of the last portion, the pressure was 235 atmospheres. The autoclave was stirred for another 16 hours at 120 C. After 12 hours the pressure became constant at a pressure of 190 atmospheres. After cooling, the excess hydrogen was released from the autoclave. Some dry hexane was added and the reaction mixture was heated for another 2 hours, at 120 C. while stirring. The product of the reaction was filtered through a G4 frit. The residue of non-converted aluminum came to 10 gm.

The hexane and the excess olefin were distilled from the filtrate first at normal pressure, then under vacuum of 12 mm. mercury, and ultirnely at 10- mm. mercury, distilling as much as possible, while the temperature rose to 150 C. The excess docosene could not be fully separated in this process. A sample of the residue tested, by reaction to n-propanol, 65% of the quantity of hydrogen calculated for aluminum-di-sec.-docosyl hydride.

270 gm. of the raw product obtained in this mannerwere heated with 20 gm. heptene-l for 15 hours, in an apparatus having magnetic stirring, to 70 C. for the purpose of conversion into a trialkylaluminum compound. Next, the alkylaluminum compound was diluted with 1.3 liters of dry hexane and oxidized with dry oxygen, in known fashion. The volatile components were distilled at normal pressure and, subsequently, at 12 mm. mercury. The residue came to 298.5 gm. By hydrolysis with the calculated quantity of dilute sulfuric acid and subsequent extraction, 276 gm. of raw alcohol were obtained. 141 gm. of the raw alcohol were distilled under high vacuum at 10 mm. mercury. 3.4 gm. heptanol-l:

Boiling point at 14 mm. Hg=7680 C. n =1.4242 83.3 gm. mixture of C alcohol and C olefin:

Boiling point at 10- mm. Hg=-120 C. Freezing point=3940 C OH number=52 Iodine number=14.4 39.2 gm. mixture of C alcohol and C olefin:

Boiling point at 10" mm. Hg=-135 C. Freezing point=4646.5 C. OH number=129 Iodine number=5.0

Example V In the experiment described below, all the operations were performed under nitrogen, where so required.

54 gm. aluminum pellets, 1.5 gm. aluminum stearate, 8 gm. aluminum di-isobutyl hydride, and 120 ml. dry hexane were ground for 15 hours in an 0.9-liter steel ball mill, about half filled with steel balls. Next, the mixture was transferred to a 1-liter agitator autoclave. The hexane was again siphoned off as much as possible. 104.4 gm. of residue were left in the autoclave. To this were added 30 gm. of pentene-Z, 1.5 gm. of aluminum stearate and 15 gm. of aluminum di-isobutyl hydride. Hydrogen was admitted at 160 atmospheres and the autoclave was heated to C. while stirring, whereby the pressure rose to 194 atmospheres. 280 gm. pentene-Z in 16 portions were pumped-into the autoclave at halfhour intervals, with the aid of a metering pump. After the addition of the last portion, the pressure was approximately 240 atmospheres. The autoclave was kept for another 6.5 hours at a temperature of 140 C. When constant pressure was achieved, the pressure amounted to 161 atmospheres. After cooling the autoclave, the excess hydrogen was released. The product was filtered through a G-4 frit. The residue in terms of non-converted aluminum came to 12 gm.

The solvent and the excess pentene-2 were distilled from the filtrate, first at normal pressure and later at 12 mm. mercury, at a maximum bath temperature of 80 C. The weight of the distillation residue was 270 gm. The residue consisted of 270 gm. of aluminum di-sec.-amylhydride.

64.5 gm. of the aluminum di-sec.-amylhydride obtained in this manner were heated together with 58 gm. decene-l for 15 hours at 70 C. in an apparatus having a magnetic stirrer. Next, the alkylaluminum compound was diluted with 1 liter dry hexane and oxidized in known manner with dry oxygen. The volatile fractions were removed by distillation, first at normal pressure and later at 12 mm. mercury. The residue consisted of 117 gm. of the oxidation product. By hydrolysis with the calculated quantity of dilute sulfuric acid and subsequent extraction, 112 gm. were obtained of a mixture consisting essentially of pentanol and decanol. Fractional distillation of this mixture through a l-meter rotary column yielded the following fractions.

21 gm. pentanol-2:

Boiling point at 760 mm. Hg=120-121 C. n 1.405 1 H number=630 12 gm. pentanol-1:

Boiling point at 760 mm. Hg=139.5 C. 11 1.4091 OH number: 628

48.7 gm. decanol-l:

Boiling point at 11 mm. Hg=118 C. n 1.43 69 OH number=343 Remarkably, in the above case a partial conversion into alkylaluminurn compounds with primary alkyl radi cals set in already at a temperature of 140 C., as evidenced by the formation of pentanol-1. Apparently, the short-chain alkyl radical is more readily converted than the long-chain radicals.

For purposes of complete isomerization, 204.5 gm. of the raw aluminum di-arnylhydride were heated together with 136.5 gm. pentene-2 for 2 hours in the autoclave, at 160 C. After cooling, the product of the reaction was freed of all volatile hydrocarbons by distillation. The maximum sump temperature was 100 C. The weight of the distillate was 73 gm. 256 gm. were left over as distillation residue. 94 gm. of the product obtained in this manner were heated to 70 C. for 15 hours in an apparatus having a magnetic stirrer, together with 26.5 gm. octene-l, for purposes of conversion of the residual Al-H bonds into Al-R bonds. After dilution with 1 liter dry hexane, the product was oxidized in the customary manner with dry oxygen. The hexane was removed by distillation. The residue consisted of 109.5 gm. of the oxidation product. This was hydrolyzed with the calculated quantity of dilute sulfuric acid. By extraction, 89 gm. were obtained of a mixture consisting largely of pentanol and octanol. By fractional distillation of the resultant alcohol mixture on a l-meter rotary column, the following fractions were obtained.

9.5 gm. pentanol-2:

Boiling point at 760 mm. Hg=120-121 C. 11 1.4060 OH number=625 40.8 gm. pentanol-1:

Boiling point at 760 mm. Hg=137.5139.8 C. 21 9: 1.4094 OH number=624 1 2 21.2 gm. octanol-lt Boiling point at 11 mm. Hg= C. 11 1.4290 OH number=429.

Various modifications of the process of the present invention may be made without departing from the spirit or scope thereof, and it is to be understood that the invention is limited only as defined in the appended claims.

We claim:

1. A process for the preparation of aluminum primary alkyl compounds wherein the primary alkyl radicals contain 5 to 30 carbon atoms which comprises reacting at a temperature between about 90 and 150 C. and a hydrogen pressure of about to 300 atmospheres metallic aluminum, hydrogen and an olefin having the formula HC=( 3-R2 wherein R and R are alkyl radicals and R is a member selected from the group consisting of hydrogen and alkyl radicals, and the sum of thte carbon atoms in R, R and R is 3 to 28, to form an aluminum secondary alkyl compound having the formula R R1 HA1 lH CH-Rz)i wherein R, R and R have the above definition, removing the hydrogen, isomerizing said aluminum secondary alkyl compound by heating at temperatures above 150 C. in the presence of more than one mol of an olefin having 2 to 30 carbon atoms per mol of said aluminum secondary alkyl compound to form said aluminum primary alkyl compounds, and recovering said compound.

2. The process of claim 1 wherein R is hydrogen and R and R are straight chain alkyls.

3. The process of claim 1 wherein the reaction of aluminum, hydrogen and the olefin is conducted .in the presence of a catalyst selected from the group consisting of alkyl halides and aluminum alkyl compounds.

4. The process of claim 1 wherein the reaction temperature is between and C.

5. The process of claim 1 wherein the isomerization is conducted at a temperature between and 220 C.

6. The process of claim 1 wherein at least 2 mols of olefin are present in the isomerization step for each mol of aluminum secondary alkyl compound to form aluminum tri-primary alkyl compounds.

7. The process of claim 1 wherein residual amounts of di-primary alkyl aluminum hydride are reacted with an u-olefin having 2 to 30 carbon atoms to form aluminum tri-primary alkyl compounds.

References Cited by the Examiner UNITED STATES PATENTS 2,695,327 11/ 1954 Ziegler et a1. 260+448 2,863,895 12/1958 Kirshenbaum et a1. 260448 2,900,402 8/ 1959v Johnson 260448 2,906,763 9/ 1959 McKinnis 260448 2,943,102 6/ 1960 Balhoflf 260448 3,016,396 1/1962 Irie et al 260448 3,100,786 8/1963 Fernal-d 260448 3,116,310 12/1963 Barie et al. 260448 FOREIGN PATENTS 1,179,056 12/ 1958 France.

OTHER REFERENCES Abstract SOV/ 62-5 8-10-21 25 of article by Zakharkin et al. in Izvestiya Akad Nauk. SSR (1958), Nr 10,

p. 1278 (in English, 2 pages).

TOBIAS E. LEVOW, Primary Examiner. 

1. A PROCESS FOR THE PREPARATION OF ALUMINUM PRIMARY ALKYL COMPOUNDS WHEREIN THE PRIMARY ALKYL RADICALS CONTAIN 5 TO 30 CARBON ATOMS WHICH COMPRISES REACTING AT A TEMPRATURE BETWEEN ABOUT 90* AND 150*C. AND A HYDROGEN PRESSURE OF ABOUT 100 TO 300 ATMOSPHERES METALLIC ALUMINUM, HYDROGEN AND AN OLEFIN HAVING THE FORMULA 